In philosophy, he is primarily known as the only source of the teachings of Epictetus whose pupil he was and author of the works Encheiridion and Diatribai based on careful notes taken from Epictetus' lectures. The Encheiridion is a manual of stoic philosophy as propounded by Epictetus. The Diatribai, generally translated as Discourses of which four books survive, holds roughly the same relationship to Epictetus' teachings as Platos dialogues do to those of Socrates, except that they are soliloquies.